Problem: Balance the following chemical equation: $ $ $\text{Mg} +$ $\text{O}_2 \rightarrow$ $\text{MgO}$
Answer: There are $2 \text{ O}$ on the left and only $1$ on the right, so multiply $\text{MgO}$ by ${2}$ $ \text{Mg} + \text{O}_2 \rightarrow {2}\text{MgO} $ That gives us $2 \text{ Mg}$ on the right and only $1$ on the left, so multiply $\text{Mg}$ by ${2}$ $ {2}\text{Mg} + \text{O}_2 \rightarrow 2\text{MgO} $ The balanced equation is: $ 2\text{Mg} + \text{O}_2 \rightarrow 2\text{MgO} $